Jim- I think I've read that Scanning Acoustic Microscopy (SAM) may not reliably detect faulty or cold solder joints, BUT it may be worth running by the people at Sonoscan Corp: in San Jose, CA 408-456-0204 in Bensenville, IL 630-766-7088, 800-950-2NDT -Michael Alderete You wrote... ------------------------------ Date: Tue, 29 Sep 1998 07:48:00 -0400 From: Jim Marsico 516-595-5879 <[log in to unmask]> Subject: Re: ASSY: BGA FAILURES Well, how about it! Does anyone have any experience using ultrasound to detect cracked solder joints? Does anyone know of a testing lab that can perform this function? Thanks again... Jim Marsico Mark wrote: Dear Jim This may be a very stupid idea, but what about using ultrasound? I believe they use ultrasound to detect microscopic fractures in mechanical assembly's and the joint between the CBGA and the solder ball is mechanical. I don't know what the ultrasound would do to the chip or the wire bonds but it may be worth some more inquiries to the component manf. I would be very interested to read how you got on. ------------------------------ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################